bug#49204: 28.0.50; How to create new file in project by project-find-file

[Giáp Trần]

Hi Developers,

I'm trying to migrate from projectile package to project(0.6.0). That
is amazing.

Today I see I can
not create a new file by using `project-find-file.

I wish we can create a new file with `project-find-file when the file is
not in candidates as `find-file function do.

Thanks.